A wireless communication system may include a macro cell for providing wide coverage with high transmit (Tx) power and a micro cell for providing small coverage with lower Tx power than the macro cell. The micro cell may be referred to as a pico cell, a femto cell, a Home NodeB (HNB), or a Home evolved-NodeB (HeNB). The micro cell may be installed, for example, in a shade region not covered by the macro cell. A user may access a local network, the public Internet, a private service provision network, etc. through the micro cell.
The micro cell may be classified into a first-type micro cell and a second-type micro cell according to whether or not user access is limited. The first-type micro cell is a Closed Subscriber Group (CSG) micro cell, and the second-type micro cell is an Open Access (OA) or Open Subscriber Group (OSG) micro cell. Only authorized users can access the CSG micro cell, and all users can access the OSG micro cell without limitation. In addition, a hybrid-access-type micro cell can provide CSG services to a user having a CSG ID, and a subscriber not contained in a CSG can also access the hybrid-access-type micro cell, but the CSG services may not be provided to the subscriber not contained in the CSG.